西部山区双排抗滑桩的机理及设计研究

MECHANICAL MODEL AND DESIGN OF DOUBLE-ROW ANTI-SLIDING PILES FOR SLOPE STABILIZATION IN MOUNTAINOUS REGIONS OF WESTERN CHINA

将公路、铁路桥梁多排桩计算的结构力学方法引入到双排抗滑桩的计算中。与其不同的是,滑动面以上存在滑坡体,而桥梁的最大冲刷线以上没有考虑这种土体的存在对滑动面以下m法的影响。本文提出了滑动面以下考虑滑坡体存在的修改m法一和修改m法二。本文还对滑动面以上前排桩桩后及后排桩桩前的土压力计算进行了实验分析研究,认为滑动面以上后排桩桩前的土压力可按静止土压力计算,滑动面以上前排桩桩后的土压力按静止土压力计算,但要增加排桩间土体的下滑力。同时,用有限杆单元法对双排桩的连梁刚度进行了分析,当满足不相互影响排桩间距的情况下,桩顶连梁与桩的刚度比不小于0.48是合适的,此时再增加连梁刚度无意义。本文认为双排桩节省费用,而且抵抗变形的能力强,值得在工程中研究和广泛应用。

The method of structural mechanics for multi - row piles that are commonly used in bridges of roads and railways is introduced to the double -row anti -sliding piles for slope stabilization. The difference is the soil body above the slide surface. However, above the scour-line of bridge, it doesnt consider the influence that the soil - body to the ＂m＂ method of under the slide surface. In this paper, ＂the perfect m -method 1＂ and ＂the perfect m -method 2＂ are presented and they consider the effect of the sliding soil body. And in this paper, the soil pressures in the back of front - row pile and in the front of back - row pile above the slide surface are researched in project application. The results are gained that the soil pressure in the front of back - row pile could be equal to the rest soil pressure, and that the soil pressure in the back of front - row pile could be equal to the summation of the rest soil pressure, and the slide force caused by the slide body between the double - row anti - sliding pile. At the same time, the finite bar element method is used to analyze the influence of connect -girder rigidity. The rigidity ratio of beam and column equal to 0.48 is found to be appropriate when the distance between double - row pile is not less than the value presented by criterion JTJ024 - 85 or 464 - 2005. The increase of the rigidity ratio is not significant, It is considered that the double - row piles are cost saving and have strong capability of resisting deformation. It＇s worthy of further investigation and extensive application.